ABSTRACT
Serine integrases catalyze precise rearrangement of DNA through site-specific recombination of small sequences of DNA called attachment (att) sites. Unlike other site-specific recombinases, the recombination reaction driven by serine integrases is highly directional and can only be reversed in the presence of an accessory protein called a recombination directionality factor (RDF). The ability to control reaction directionality has led to the development of serine integrases as tools for controlled rearrangement and modification of DNA in synthetic biology, gene therapy, and biotechnology. This review discusses recent advances in serine integrase technologies focusing on their applications in genome engineering, DNA assembly, and logic and data storage devices.
Subject(s)
Attachment Sites, Microbiological/physiology , DNA , Integrases , Recombination, Genetic/physiology , Synthetic Biology , DNA/genetics , DNA/metabolism , Integrases/genetics , Integrases/metabolismABSTRACT
Synthetic biology requires effective methods to assemble DNA parts into devices and to modify these devices once made. Here we demonstrate a convenient rapid procedure for DNA fragment assembly using site-specific recombination by C31 integrase. Using six orthogonal attP/attB recombination site pairs with different overlap sequences, we can assemble up to five DNA fragments in a defined order and insert them into a plasmid vector in a single recombination reaction. C31 integrase-mediated assembly is highly efficient, allowing production of large libraries suitable for combinatorial gene assembly strategies. The resultant assemblies contain arrays of DNA cassettes separated by recombination sites, which can be used to manipulate the assembly by further recombination. We illustrate the utility of these procedures to (i) assemble functional metabolic pathways containing three, four or five genes; (ii) optimize productivity of two model metabolic pathways by combinatorial assembly with randomization of gene order or ribosome binding site strength; and (iii) modify an assembled metabolic pathway by gene replacement or addition.
